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Composite Fish Culture
Fish & Aquatic Ecology Unit
Department of Zoology
Rajiv Gandhi University
EATING 100g FISH A DAY KEEP THE DOCTORS AWAY ……………
•World fish consumption -16.3Kg• Indian fish consumption – 9.0Kg
Why fish culture?
• Provides nutrition
• Provides income
• Provides employment
Where, fish culture?
• Low lying areas
• Perennial water source
• Accessibility
• Free from pollutants
Types of Culture
Monoculture
Polyculture
What is Composite fish culture?
Culture of different fast-growing and compatible species having different feeding habits, in the same pond is called “composite fish culture” or “polyculture” or “mixed farming”.
According to the depth, a pond can be divided in to three distinct zones
I. Upper surface zone
II. Middle column zone
III. Bottom zone
A particular species exploits a particular zone
Surface
Column
Bottom
Catla Silver carp
Rohu Grass carp
Mrigal Common carp
In this multi-species culture system, the fishes utilize all the ecological niches of the pond 1. Catla (Catla catla) – surface feeder
2. Rohu (Labeo rohita) – column feeder
3. Mrigal (Cirrhinus mrigala) – bottom feeder
4. Grass carp (Ctenopharyngodon idella) -
Feeds on macro-vegetation
5. Silver carp (Hypophthalmichthys molitrix) –
surface feeder
6. Common carp (Cyprinus carpio) – bottom
feeder
Surface feeders
Catla
Silver carp
Column feeders
Rohu
Grass carp
Bottom feeders
Mrigal
Common carp
Management of Composite Fish Culture Pond
Management practices
• Pre-stocking
• Stocking
• Post-stocking
Pre-stocking managementa) Weed clearanceWhy?• Aquatic weeds reduce the living space available
for fish• Prevents entry of sunlight into the pond• Consume nutrients from the pond – affects the
production of fish food organisms (plankton)• Provides shelter to fish enemies• Causes obstruction for harvesting of fish• Excessive growth – upsets oxygen balance
Unmanaged weed infested pond
Managed pond
b) Eradication of unwanted fish
Why?
• The unwanted fish compete for food, space and oxygen with the fingerlings of cultivable carps
• Some fishes may prey upon the carp fingerlings
How?
• Dewatering ensures complete removal of unwanted fish
• In ponds, where dewatering is not possible, mahua oil cake @ 2000-2500 kg/ha-m depth is recommended
Dry the pond until the bottom gets cracks. Help in eradication of unwanted and harmful micro-organisms, removal of some toxic gases from pond bottom, kill the parasites.
Unwanted fish for CFC
c) ManuringWhy?• Manuring ensures production of natural fish
food in the pond (phytoplankton & zooplankton)
How?• If mahua is applied, Raw Cow Dung (RCD)
should be applied 7 days after mahua application @ 5000 kg/ha
• If mahua is not applied, RCD should be applied @ 10,000 kg/ha, 15 days before the stocking of fish seeds
RAW COW DUNG (RCD)
d) Liming
• Liming is done after 7 days of RCD application
Why?
• Liming is done to correct the acidity
• It also helps to keep the pond hygienic
pH of soil Type of soil Dose of lime (kg/ha)
4.5-5.0 Highly acidic 2000
5.0-6.0 Moderately acidic 1200
6.0-6.5 Mildly acidic 1000
6.5-7.0 Near neutral 400
7.0-7.5 Mildly alkaline 200
Dose of lime for different soil types
Stocking
a) Stocking density
• A stocking density of 7500 nos. of fingerlings/ha is recommended
• A stocking density of 6000 fingerlings/ha would be ideal when the rearing period is limited to about 8-10 months
b) Species combination• In North Eastern Region, the species combination and
proportion depends on the altitude of the place• In lower altitudes (upto 2500 ft msl) with warm
temperature – 20% Catla : 20% Rohu : 15% Mrigal : 20% Silver carp : 10% Grass carp : 15% Common carp
• In medium altitudes (upto 3500 ft msl) - 20% Catla : 10% Rohu : 10% Mrigal : 30% Silver carp : 10% Grass carp : 20% Common carp
• In higher altitudes (above 3500 ft msl & below 4500 ft msl) - 40% Silver carp : 25% Grass carp : 35% Common carp
c) Stocking size
• Fingerlings of 100-150 mm size are ideal for stocking, particularly in the colder climatic conditions of NEH Region
Post-stocking management
a) Supplementary feeding
• Rice polish and mustard oil cake is fed to the fishes in a ratio of 1:1 by weight @ 3% of their body weight of fishes
• The feed can be adjusted by regular monitoring of food consumption from the feeding trays
• Feed is administered twice daily – morning and evening
• The feed ingredients – made a dough - placed in feeding basket
• For grass carp, chopped green vegetation are provided on feeding trays made of bamboo
• 10-15 trays will be required for a 1 ha. pond
• Aquatic and terrestrial vegetation including fodder grasses and vegetable wastes can be supplemented for grass carp
• Grass carp is fed at least 1hr prior to the feeding of rice polish+M.O.Cake
• Feed for the grass carp can be provided on a feeding tray (made of split bamboo in a rectangular form)
A view of the feeding basket
Feeding in progress
b) Fertilization
• Periodic organic and inorganic manuring is essential for production of fish food organisms in the pond
• Cow dung is applied as organic manure @ 1000 kg/ha/month.
• Urea @ 25 kg/ha/month and single superphosphate @ 30 kg/ha/month are applied as inorganic fertilizers
• The inorganic manure should be applied by mixing with mud to facilitate slow leaching
Mode of application of inorganic fertilizer
Inorganic manure is normally applied after 15 days of application of organic manure
Fertilization should not be done during cloudy weather and when algal blooms appears
c) Liming
• Liming is done once in a month @ 25 kg/ha (300 kg/ha/yr), two days after the application of organic manure
Mixing of lime
Application of lime
d) Raking
• Raking of pond bottom is done, a day after liming
• Raking can be done by netting or by dragging branches of tree or by a rope tied with bricks
• Raking helps in proper mixing of lime with the bottom sediment and also helps in the release of obnoxious gases trapped at the bottom
Growth and health care
• The growth and health of fish is to be regularly monitored by periodic netting, atleast once in two months
• If feed provided is not consumed, either the fish are suffering from some disease or the water quality is deteriorated
• Quantity of feed needs to be adjusted based on the growth increment of fish
• A bath in potassium permanganate solution is necessary for the netted fishes, before releasing back into the pond
Potassium permanganate bath for netted fish
Checking the growth of fish
• If managed properly, a fish production of 2000-3000 kg/ha/yr can be obtained, with a net profit of Rs.40,000-45,000/- can be expected
Harvesting and Production
Generally practiced for 12 months
Catla 800gm-1kg
Rohu 600-800gm
Mrigal 400-600gm
Silver carp 1.0-1.2kg
Grass carp 1.0-1.5kg
Common carp 800gm-1.0kg
Economics (12 months culture period in a 1ha pond)
SNo
Items Cost (Rs.)
A.Expenditure
1 Weed clearance 1,000.00
2 Mahua Oil Cake (2500kg @ Rs.4.50/kg)
11,250.00
3 Lime (1500kg@ Rs.6.00.kg) 9,000.00
4 Cow dung (20,000kg @ Rs. 30.00/Quintal)
6,000.00
5 Urea (250kg @ Rs.6.00/kg) 1,500.00
6 SSP (300kg @ Rs.5.00/kg) 1,500.00
7 Fingerlings (@7500 nos./ha) 15,000.00
8 Feed i) Rice bran (2625kg @ Rs.4.00/kg)
10,500.00
ii) M.O.C (2625kg @ Rs.7.00/kg)
18,375.00
9 Netting 2,000.00
10
Miscellaneous 5,000.00
Total Expenditure 81,125.00
B.Return
2500kg fish @ Rs.50/kg 1,25,000.00
C Profit (B-A) 43,875.00
Fish for healthFish for incomeFish for enjoymentFish for hobbyFISH FOR ALLGROW MORE FISH FOR A HEALTHY TOMORROW